Dandelion Derived Nitrogen-Doped Hollow Carbon Host for Encapsulating Sulfur in Lithium Sulfur Battery

Biomass derivative carbonaceous materials are extremely fascinating for developing advanced energy storage devices according to unique architecture. Here, inspired by dandelion with consecutive hollow channel, nitrogen-doped hollow carbon framework (NHCF) as sulfur host was obtained via a simple thermal calcination in ammonia atmosphere for lithium–sulfur battery. The NHCF can effectively confine polysulfides and electrochemical reaction within the hollow channel and expedite lithium ion diffusion and electrode transport through porous nitrogen-doped carbon rampart. With this strategy, a high-level active sulfur loading of 80% and high sulfur utilization can be realized. As a result, the NHCF/S delivered an advanced initial capacity of 950 mAh g–1 at the rate of 0.5 C with small capacity fading rates of 0.049% per cycle after 500 cycles. Additionally, an average reversible areal capacity of nearly 5 mAh cm–2 was realized under raised sulfur mass loading of 5.5 mg cm–2. This superior electrochemical energy storage property endows renewable biomass derived carbon host with promising potential for low-cost rechargeable battery application